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Table of Contents Index to Financial Statements

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission
File Number

Registrant,
State of Incorporation,
Address and Telephone Number

I.R.S. Employer
Identification No.

1-3526

The Southern Company

58-0690070

(A Delaware Corporation)

30 Ivan Allen Jr. Boulevard, N.W.

Atlanta, Georgia 30308

(404) 506-5000

1-3164

Alabama Power Company

63-0004250

(An Alabama Corporation)

600 North 18th Street

Birmingham, Alabama 35203

(205) 257-1000

1-6468

Georgia Power Company

58-0257110

(A Georgia Corporation)

241 Ralph McGill Boulevard, N.E.

Atlanta, Georgia 30308

(404) 506-6526

001-11229

Mississippi Power Company

64-0205820

(A Mississippi Corporation)

2992 West Beach Boulevard

Gulfport, Mississippi 39501

(228) 864-1211

001-37803

Southern Power Company

58-2598670

(A Delaware Corporation)

30 Ivan Allen Jr. Boulevard, N.W.

Atlanta, Georgia 30308

(404) 506-5000

1-14174

Southern Company Gas

58-2210952

(A Georgia Corporation)

Ten Peachtree Place, N.E.

Atlanta, Georgia 30309

(404) 584-4000

Table of Contents Index to Financial Statements

Securities registered pursuant to Section 12(b) of the Act:


Registrant	Title of Each Class	Trading Symbol(s)	Name of Each Exchange on Which Registered
The Southern Company	Common Stock, par value $5 per share	SO	New York Stock Exchange
			(NYSE)
The Southern Company	Series 2017B 5.25% Junior Subordinated Notes due 2077	SOJC	NYSE
The Southern Company	Series 2020A 4.95% Junior Subordinated Notes due 2080	SOJD	NYSE
The Southern Company	Series 2020C 4.20% Junior Subordinated Notes due 2060	SOJE	NYSE
The Southern Company	Series 2021B 1.875% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2081	SO 81	NYSE
The Southern Company	Series 2025A 6.50% Junior Subordinated Notes due 2085	SOJF	NYSE
Georgia Power Company	Series 2017A 5.00% Junior Subordinated Notes due 2077	GPJA	NYSE
Southern Power Company	Series 2016B 1.850% Senior Notes due 2026	SO/26A	NYSE

Indicate by check mark whether the registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. Yes þ No ¨

Indicate by check mark whether the registrants have submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrants were required to submit such files). Yes þ No ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Registrant

Large Accelerated Filer

Accelerated
Filer

Non-accelerated Filer

Smaller
Reporting
Company

Emerging
Growth
Company

The Southern Company

Alabama Power Company

Georgia Power Company

Mississippi Power Company

Southern Power Company

Southern Company Gas

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No þ (Response applicable to all registrants.)


Registrant	Description of Common Stock	Shares Outstanding at September 30, 2025
The Southern Company	Par Value $5 Per Share	1,101,104,843
Alabama Power Company	Par Value $40 Per Share	30,537,500
Georgia Power Company	Without Par Value	9,261,500
Mississippi Power Company	Without Par Value	1,121,000
Southern Power Company	Par Value $0.01 Per Share	1,000
Southern Company Gas	Par Value $0.01 Per Share	100

This combined Form 10-Q is separately filed by The Southern Company, Alabama Power Company, Georgia Power Company, Mississippi Power Company, Southern Power Company, and Southern Company Gas. Information contained herein relating to any individual registrant is filed by such registrant on its own behalf. Each registrant makes no representation as to information relating to the other registrants.

Table of Contents Index to Financial Statements

TABLE OF CONTENTS


		Page

	Definitions	4
	Cautionary Statement Regarding Forward-Looking Information	7

	PART I—FINANCIAL INFORMATION

Item 1.	Financial Statements (Unaudited)	9
Item 2.	Management's Discussion and Analysis of Financial Condition and Results of Operations	97
Item 3.	Quantitative and Qualitative Disclosures about Market Risk	150
Item 4.	Controls and Procedures	150

	PART II—OTHER INFORMATION

Item 1.	Legal Proceedings	151
Item 1A.	Risk Factors	151
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	Inapplicable
Item 3.	Defaults Upon Senior Securities	Inapplicable
Item 4.	Mine Safety Disclosures	Inapplicable
Item 5.	Other Information	151
Item 6.	Exhibits	151

	Signatures	155

Table of Contents Index to Financial Statements

DEFINITIONS


Term			Meaning
2022 ARP			Alternate Rate Plan approved by the Georgia PSC in 2022 for Georgia Power for the years 2023 through 2025
2023 IRP Update			Georgia Power's updated IRP filed in 2023 and approved by the Georgia PSC in April 2024 as modified by a stipulation among Georgia Power, the staff of the Georgia PSC, and certain intervenors
2024 ELG Rule			Final rule published by the EPA in May 2024 revising the steam effluent guidelines
2024 GHG Rules			Final rules published by the EPA in May 2024 for existing fossil fuel-fired steam electric generating units and new fossil fuel-fired combustion turbines and combined cycle generation facilities
2024 Legacy Rule			Final rule published by the EPA in May 2024 related to legacy surface impoundments and CCR management units
AFUDC			Allowance for funds used during construction
AGL Services Company			AGL Services Company, Inc., the Southern Company Gas system service company and a wholly-owned subsidiary of Southern Company Gas
Alabama Power			Alabama Power Company
ARO			Asset retirement obligation

Atlanta Gas Light			Atlanta Gas Light Company, a wholly-owned subsidiary of Southern Company Gas


CAMT			Corporate alternative minimum tax

CCR			Coal combustion residuals
CCR Rule			Disposal of Coal Combustion Residuals from Electric Utilities final rule published by the EPA in 2015
Chattanooga Gas			Chattanooga Gas Company, a wholly-owned subsidiary of Southern Company Gas
Clean Air Act			Clean Air Act Amendments of 1990

COD			Commercial operation date
CODM			Chief operating decision maker


CWIP			Construction work in progress
Dalton			City of Dalton, Georgia, an incorporated municipality in the state of Georgia, acting by and through its Board of Water, Light, and Sinking Fund Commissioners
Dalton Pipeline			A pipeline facility in Georgia in which Southern Company Gas has a 50% undivided ownership interest
DOE			U.S. Department of Energy
ECCR			Georgia Power's Environmental Compliance Cost Recovery tariff
ECO Plan			Mississippi Power's environmental compliance overview plan
ELG			Effluent limitations guidelines
EPA			U.S. Environmental Protection Agency


FCC			Federal Communications Commission
FERC			Federal Energy Regulatory Commission
FFB			Federal Financing Bank
Fitch			Fitch Ratings, Inc.
FP&L			Florida Power and Light Company
Form 10-K			Annual Report on Form 10-K of Southern Company, Alabama Power, Georgia Power, Mississippi Power, Southern Power, and Southern Company Gas for the year ended December 31, 2024, as applicable
GAAP			U.S. generally accepted accounting principles
Georgia Power			Georgia Power Company
GHG			Greenhouse gas


Heating Degree Days			A measure of weather, calculated when the average daily temperatures are less than 65 degrees Fahrenheit
Heating Season			The period from November through March when Southern Company Gas' natural gas usage and operating revenues are generally higher
HLBV			Hypothetical liquidation at book value

Table of Contents Index to Financial Statements

DEFINITIONS

(continued)


Term			Meaning
IGCC			Integrated coal gasification combined cycle, the technology originally approved for Mississippi Power's Kemper County energy facility
IIC			Intercompany Interchange Contract

Internal Revenue Code			Internal Revenue Code of 1986, as amended
IRP			Integrated resource plan
IRS			Internal Revenue Service
ITC			Investment tax credit
KWH			Kilowatt-hour
LIFO			Last-in, first-out
LTSA			Long-term service agreement
MEAG Power			Municipal Electric Authority of Georgia
Mississippi Power			Mississippi Power Company
mmBtu			Million British thermal units
Moody's			Moody's Investors Service, Inc.
MRA			Municipal and Rural Associations
MW			Megawatt
natural gas distribution utilities			Southern Company Gas' natural gas distribution utilities (Nicor Gas, Atlanta Gas Light, Virginia Natural Gas, and Chattanooga Gas)
NCCR			Georgia Power's Nuclear Construction Cost Recovery tariff
NDR			Alabama Power's Natural Disaster Reserve
Nicor Gas			Northern Illinois Gas Company, a wholly-owned subsidiary of Southern Company Gas

NRC			U.S. Nuclear Regulatory Commission

OCI			Other comprehensive income
OPC			Oglethorpe Power Corporation (an electric membership corporation)
PEP			Mississippi Power's Performance Evaluation Plan
PowerSecure			PowerSecure, Inc., a wholly-owned subsidiary of Southern Company
PPA			Power purchase agreements, as well as, for Southern Power, contracts for differences that provide the owner of a renewable facility a certain fixed price for the electricity sold to the grid

PSC			Public Service Commission
PTC			Production tax credit
Rate CNP			Alabama Power's Rate Certificated New Plant, consisting of Rate CNP New Plant, Rate CNP Compliance, Rate CNP PPA, and Rate CNP Depreciation
Rate ECR			Alabama Power's Rate Energy Cost Recovery

Rate RSE			Alabama Power's Rate Stabilization and Equalization
Registrants			Southern Company, Alabama Power, Georgia Power, Mississippi Power, Southern Power Company, and Southern Company Gas
ROE			Return on equity
S&P			S&P Global Ratings, a division of S&P Global Inc.
SAVE			Steps to Advance Virginia's Energy, an infrastructure replacement program at Virginia Natural Gas
SCS			Southern Company Services, Inc., the Southern Company system service company and a wholly-owned subsidiary of Southern Company
SEC			U.S. Securities and Exchange Commission
SEGCO			Southern Electric Generating Company, 50% owned by each of Alabama Power and Georgia Power
SNG			Southern Natural Gas Company, L.L.C., a pipeline system in which Southern Company Gas has a 50% ownership interest
SOFR			Secured Overnight Financing Rate
Southern Company			The Southern Company
Southern Company Gas			Southern Company Gas and its subsidiaries

Table of Contents Index to Financial Statements

DEFINITIONS

(continued)


Term			Meaning
Southern Company Gas Capital			Southern Company Gas Capital Corporation, a wholly-owned subsidiary of Southern Company Gas
Southern Company power pool			The operating arrangement whereby the integrated generating resources of the traditional electric operating companies and Southern Power (excluding subsidiaries) are subject to joint commitment and dispatch in order to serve their combined load obligations
Southern Company system			Southern Company, the traditional electric operating companies, Southern Power, Southern Company Gas, SEGCO, Southern Nuclear, SCS, Southern Linc, PowerSecure, and other subsidiaries
Southern Holdings			Southern Company Holdings, Inc., a wholly-owned subsidiary of Southern Company
Southern Linc			Southern Communications Services, Inc., a wholly-owned subsidiary of Southern Company, doing business as Southern Linc
Southern Nuclear			Southern Nuclear Operating Company, Inc., a wholly-owned subsidiary of Southern Company
Southern Power			Southern Power Company and its subsidiaries
SouthStar			SouthStar Energy Services, LLC (a Marketer), a wholly-owned subsidiary of Southern Company Gas
SP Solar			SP Solar Holdings I, LP, a limited partnership indirectly owning substantially all of Southern Power's solar and battery energy storage facilities, in which Southern Power has a 67% ownership interest
SP Wind			SP Wind Holdings II, LLC, a holding company owning a portfolio of eight operating wind facilities, in which Southern Power is the controlling partner in a tax equity arrangement
SRR			Mississippi Power's System Restoration Rider, a tariff for retail property damage cost recovery and reserve
Subsidiary Registrants			Alabama Power, Georgia Power, Mississippi Power, Southern Power, and Southern Company Gas

traditional electric operating companies			Alabama Power, Georgia Power, and Mississippi Power
U.S. Treasury			U.S. Department of the Treasury
VIE			Variable interest entity
Virginia Commission			Virginia State Corporation Commission
Virginia Natural Gas			Virginia Natural Gas, Inc., a wholly-owned subsidiary of Southern Company Gas
Vogtle Owners			Georgia Power, OPC, MEAG Power, and Dalton

Table of Contents Index to Financial Statements

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

This Quarterly Report on Form 10-Q contains forward-looking statements. Forward-looking statements include, among other things, statements concerning regulated rates, the strategic goals for the business, customer and sales growth, economic conditions, including inflation, cost recovery and other rate actions, current and proposed environmental regulations and related compliance plans and estimated expenditures, pending or potential litigation matters, access to sources of capital, financing activities, completion dates and costs of construction projects, matters related to the abandonment of the Kemper IGCC, completion of announced acquisitions, filings with state and federal regulatory authorities, and estimated construction plans and expenditures. In some cases, forward-looking statements can be identified by terminology such as "may," "will," "could," "would," "should," "expects," "plans," "anticipates," "believes," "estimates," "projects," "predicts," "potential," or "continue" or the negative of these terms or other similar terminology. There are various factors that could cause actual results to differ materially from those suggested by the forward-looking statements; accordingly, there can be no assurance that such indicated results will be realized. These factors include:

•the impact of recent and future federal and state regulatory changes, including tax, environmental, and other laws and regulations to which Southern Company and its subsidiaries are subject, as well as changes in application of existing laws, regulations, and guidance;

•the extent and timing of costs and legal requirements related to CCR;

•current and future litigation or regulatory investigations, proceedings, or inquiries, including litigation related to the Kemper County energy facility;

•the effects, extent, and timing of the entry of additional competition in the markets in which Southern Company's subsidiaries operate, including from the development and deployment of alternative energy sources;

•variations in demand for electricity and natural gas;

•available sources and costs of natural gas and other fuels and commodities;

•the ability to complete necessary or desirable pipeline expansion or infrastructure projects, limits on pipeline capacity, public and policymaker support for such projects, and operational interruptions to natural gas distribution and transmission activities;

•transmission constraints;

•the ability to control costs and avoid cost and schedule overruns during the development, construction, and operation of facilities or other projects due to challenges which include, but are not limited to, changes in labor costs, availability, and productivity; challenges with the management of contractors or vendors; subcontractor performance; adverse weather conditions; shortages, delays, increased costs, or inconsistent quality of equipment, materials, and labor; contractor or supplier delay; the impacts of inflation and tariffs; delays due to judicial or regulatory action; nonperformance under construction, operating, or other agreements; operational readiness, including specialized operator training and required site safety programs; engineering or design problems or any remediation related thereto; design and other licensing-based compliance matters; challenges with start-up activities, including major equipment failure, or system integration; and/or operational performance; challenges related to future pandemic health events; continued public and policymaker support for projects; environmental and geological conditions; delays or increased costs to interconnect facilities to transmission grids; and increased financing costs as a result of changes in interest rates or as a result of project delays;

•legal proceedings and regulatory approvals and actions related to past, ongoing, and proposed construction projects, including state PSC or other applicable state regulatory agency approvals and FERC and NRC actions;

•the ability to construct facilities in accordance with the requirements of permits and licenses, to satisfy any environmental performance standards and the requirements of tax credits and other incentives, and to integrate facilities into the Southern Company system upon completion of construction;

•investment performance of the employee and retiree benefit plans and nuclear decommissioning trust funds;

•advances in technology, including the pace and extent of development of low- to no-carbon energy and battery energy storage technologies and negative carbon concepts;

•performance of counterparties under ongoing renewable energy partnerships and development agreements;

•state and federal rate regulations and the impact of pending and future rate cases and negotiations, including rate actions relating to ROE, equity ratios, additional generating capacity and transmission facilities, extension of retirement dates for fossil fuel plants, and fuel and other cost recovery mechanisms;

•the ability to successfully operate the traditional electric operating companies', SEGCO's, and Southern Power's generation, transmission, distribution, and battery energy storage facilities, as applicable, and Southern Company Gas' natural gas distribution and storage facilities and the successful performance of necessary corporate functions;

Table of Contents Index to Financial Statements

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

(continued)

•the inherent risks involved in operating nuclear generating facilities;

•the inherent risks involved in generation, transmission, and distribution of electricity and transportation and storage of natural gas, including accidents, explosions, fires, mechanical problems, discharges or releases of toxic or hazardous substances or gases, and other environmental risks;

•the performance of projects undertaken by the non-utility businesses and the success of efforts to invest in and develop new opportunities;

•internal restructuring or other restructuring options that may be pursued;

•potential business strategies, including acquisitions or dispositions of assets or businesses, or interests therein, which cannot be assured to be completed or beneficial to Southern Company or its subsidiaries;

•the ability of counterparties of Southern Company and its subsidiaries to make payments as and when due and to perform as required;

•the ability to obtain new short- and long-term contracts with wholesale customers;

•the direct or indirect effect on the Southern Company system's business resulting from cyber intrusion or physical attack and the threat of cyber and physical attacks;

•global and U.S. economic conditions, including impacts from geopolitical conflicts, recession, inflation, changes in trade policies (including tariffs and other trade measures) of the United States and other countries, interest rate fluctuations, and financial market conditions, and the results of financing efforts;

•access to capital markets and other financing sources;

•changes in Southern Company's and any of its subsidiaries' credit ratings;

•the ability of the traditional electric operating companies to obtain additional generating capacity (or sell excess generating capacity) at competitive prices;

•catastrophic events such as fires, earthquakes, explosions, floods, tornadoes, hurricanes and other storms, droughts, pandemic health events, political unrest, wars, or other similar occurrences;

•the direct or indirect effects on the Southern Company system's business resulting from incidents affecting the U.S. electric grid, natural gas pipeline infrastructure, or operation of generating or storage resources;

•impairments of goodwill or long-lived assets;

•the effect of accounting pronouncements issued periodically by standard-setting bodies; and

•other factors discussed elsewhere herein and in other reports (including the Form 10-K) filed by the Registrants from time to time with the SEC.

The Registrants expressly disclaim any obligation to update any forward-looking statements.

Table of Contents Index to Financial Statements

PART I

Item 1. Financial Statements (Unaudited).


			Page
The Southern Company and Subsidiary Companies:
Condensed Consolidated Statements of Income			10
Condensed Consolidated Statements of Comprehensive Income			11
Condensed Consolidated Statements of Cash Flows			12
Condensed Consolidated Balance Sheets			13
Condensed Consolidated Statements of Stockholders' Equity			15

Alabama Power Company:
Condensed Statements of Income			17
Condensed Statements of Comprehensive Income			17
Condensed Statements of Cash Flows			18
Condensed Balance Sheets			19
Condensed Statements of Common Stockholder's Equity			21

Georgia Power Company:
Condensed Statements of Income			22
Condensed Statements of Comprehensive Income			22
Condensed Statements of Cash Flows			23
Condensed Balance Sheets			24
Condensed Statements of Common Stockholder's Equity			26

Mississippi Power Company:
Condensed Statements of Income			27
Condensed Statements of Comprehensive Income			27
Condensed Statements of Cash Flows			28
Condensed Balance Sheets			29
Condensed Statements of Common Stockholder's Equity			31

Southern Power Company and Subsidiary Companies:
Condensed Consolidated Statements of Income			32
Condensed Consolidated Statements of Comprehensive Income (Loss)			32
Condensed Consolidated Statements of Cash Flows			33
Condensed Consolidated Balance Sheets			34
Condensed Consolidated Statements of Stockholders' Equity			36

Southern Company Gas and Subsidiary Companies:
Condensed Consolidated Statements of Income			38
Condensed Consolidated Statements of Comprehensive Income			38
Condensed Consolidated Statements of Cash Flows			39
Condensed Consolidated Balance Sheets			40
Condensed Consolidated Statements of Stockholder's Equity			42

Combined Notes to the Condensed Financial Statements			43

Table of Contents Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2025		2024		2025		2024
	(in millions)				(in millions)
Operating Revenues:
Retail electric revenues	$	5,707	$	5,366	$	15,065	$	13,793
Wholesale electric revenues	832		721		2,257		1,919
Other electric revenues	262		222		724		631
Natural gas revenues (includes alternative revenue programs of $(5), $1, $(32), and $46, respectively)	734		682		3,552		3,220
Other revenues	288		283		974		820
Total operating revenues	7,823		7,274		22,572		20,383
Operating Expenses:
Fuel	1,345		1,146		3,753		3,174
Purchased power	259		249		769		669
Cost of natural gas	116		98		1,046		852
Cost of other sales	156		166		522		464
Other operations and maintenance	1,643		1,662		4,948		4,522
Depreciation and amortization	1,422		1,210		4,030		3,537
Taxes other than income taxes	288		375		1,136		1,155




Total operating expenses	5,229		4,906		16,204		14,373
Operating Income	2,594		2,368		6,368		6,010
Other Income and (Expense):
Allowance for equity funds used during construction	90		58		243		167
Earnings from equity method investments	33		31		76		107
Interest expense, net of amounts capitalized	(755)		(692)		(2,343)		(2,050)

Other income (expense), net	149		147		459		450
Total other income and (expense)	(483)		(456)		(1,565)		(1,326)
Earnings Before Income Taxes	2,111		1,912		4,803		4,684
Income taxes	404		377		973		890
Consolidated Net Income	1,707		1,535		3,830		3,794


Net loss attributable to noncontrolling interests	(4)		—		(95)		(73)
Consolidated Net Income Attributable to Southern Company	$	1,711	$	1,535	$	3,925	$	3,867
Common Stock Data:
Earnings per share -
Basic	$	1.55	$	1.40	$	3.56	$	3.53
Diluted	$	1.54	$	1.39	$	3.54	$	3.51
Average number of shares of common stock outstanding (in millions)
Basic	1,102		1,097		1,101		1,096
Diluted	1,110		1,103		1,108		1,102

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2025		2024		2025		2024
	(in millions)				(in millions)
Consolidated Net Income	$	1,707	$	1,535	$	3,830	$	3,794
Other comprehensive income (loss):
Qualifying hedges:
Changes in fair value, net of tax of $(5), $(1), $12, and $(2), respectively	(13)		(2)		36		(5)
Reclassification adjustment for amounts included in net income, net of tax of $2, $(2), $(12), and $14, respectively	5		(8)		(38)		39
Pension and other postretirement benefit plans:
Benefit plan net gain (loss), net of tax of $—, $—, $—, and $1, respectively	—		—		1		3
Reclassification adjustment for amounts included in net income, net of tax of $—, $—, $—, and $—, respectively	—		1		—		1
Total other comprehensive income (loss)	(8)		(9)		(1)		38
Comprehensive Income	1,699		1,526		3,829		3,832


Comprehensive loss attributable to noncontrolling interests	(4)		—		(95)		(73)
Consolidated Comprehensive Income Attributable to Southern Company	$	1,703	$	1,526	$	3,924	$	3,905

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)


	For the Nine Months Ended September 30,
	2025		2024
	(in millions)
Operating Activities:
Consolidated net income	$	3,830	$	3,794
Adjustments to reconcile consolidated net income to net cash provided from operating activities —
Depreciation and amortization, total	4,425		3,916
Deferred income taxes	355		607

Allowance for equity funds used during construction	(243)		(167)

Pension, postretirement, and other employee benefits	(414)		(391)
Settlement of asset retirement obligations	(471)		(405)
Stock based compensation expense	124		120










Storm damage cost recovery – long-term	(262)		—
Other, net	(22)		(121)
Changes in certain current assets and liabilities —
-Receivables	200		(233)
-Retail fuel cost under recovery	439		843

-Fossil fuel for generation	121		143
-Materials and supplies	18		(195)



-Other current assets	(187)		(181)
-Accounts payable	(747)		(161)
-Accrued taxes	432		179
-Accrued compensation	(126)		(90)





-Other current liabilities	(267)		(43)
Net cash provided from operating activities	7,205		7,615
Investing Activities:


Property additions	(8,452)		(6,206)


Business acquisition	(635)		—
Nuclear decommissioning trust fund purchases	(1,212)		(1,070)
Nuclear decommissioning trust fund sales	1,212		1,070
Proceeds from dispositions	1		370
Cost of removal, net of salvage	(479)		(444)
Change in construction payables, net	69		(119)


Other investing activities	(103)		(279)
Net cash used for investing activities	(9,599)		(6,678)
Financing Activities:
Decrease in notes payable, net	(993)		(1,264)
Proceeds —
Long-term debt	10,269		5,321

Short-term borrowings	200		700
Common stock	90		112

Redemptions and repurchases —
Long-term debt	(2,383)		(2,167)



Short-term borrowings	—		(1,020)

Distributions to noncontrolling interests	(118)		(108)

Payment of common stock dividends	(2,254)		(2,220)

Other financing activities	(176)		(157)
Net cash provided from (used for) financing activities	4,635		(803)
Net Change in Cash, Cash Equivalents, and Restricted Cash	2,241		134
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	1,101		921
Cash, Cash Equivalents, and Restricted Cash at End of Period	$	3,342	$	1,055
Supplemental Cash Flow Information:
Cash paid during the period for —
Interest (net of $97 and $76 capitalized for 2025 and 2024, respectively)	$	2,173	$	2,015
Income taxes, net (excludes credit transfers)	231		131
Noncash transactions —
Accrued property additions at end of period	1,177		937




Right-of-use assets obtained under operating leases	131		126
Right-of-use assets obtained under finance leases	17		1
Reassessment of right-of-use assets under operating leases	—		(7)

Issuance of common stock under dividend reinvestment plan	167		123

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)


Assets	At September 30, 2025		At December 31, 2024
	(in millions)
Current Assets:
Cash and cash equivalents	$	3,341	$	1,070

Receivables —
Customer accounts	2,304		2,228

Unbilled revenues	685		825
Under recovered fuel clause revenues	517		713

Other accounts and notes	476		597
Accumulated provision for uncollectible accounts	(79)		(74)
Materials and supplies	2,158		2,178
Fossil fuel for generation	682		803
Natural gas for sale	415		388

Prepaid expenses	324		294

Assets from risk management activities, net of collateral	56		39
Regulatory assets – asset retirement obligations	353		353


Other regulatory assets	793		804
Other current assets	602		476
Total current assets	12,627		10,694
Property, Plant, and Equipment:
In service	143,189		137,143
Less: Accumulated depreciation	42,793		40,126
Plant in service, net of depreciation	100,396		97,017
Other utility plant, net	331		410
Nuclear fuel, at amortized cost	914		873
Construction work in progress	9,239		6,389
Total property, plant, and equipment	110,880		104,689
Other Property and Investments:
Goodwill	5,161		5,161
Nuclear decommissioning trusts, at fair value	2,884		2,621
Equity investments in unconsolidated subsidiaries	1,303		1,416
Other intangible assets, net of amortization of $436 and $412, respectively	308		332

Miscellaneous property and investments	696		668
Total other property and investments	10,352		10,198
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	1,378		1,386
Deferred charges related to income taxes	911		889
Prepaid pension costs	2,982		2,674

Unamortized loss on reacquired debt	191		203
Deferred under recovered fuel clause revenues	197		485
Regulatory assets – asset retirement obligations, deferred	5,047		5,458
Other regulatory assets, deferred	7,361		7,037


Other deferred charges and assets	1,322		1,467
Total deferred charges and other assets	19,389		19,599
Total Assets	$	153,248	$	145,180

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)


Liabilities and Stockholders' Equity	At September 30, 2025		At December 31, 2024
	(in millions)
Current Liabilities:
Securities due within one year	$	7,541	$	4,718

Notes payable	144		1,338

Accounts payable	3,017		3,701
Customer deposits	489		486
Accrued taxes —
Accrued income taxes	456		57

Other accrued taxes	966		997
Accrued interest	602		682

Accrued compensation	1,206		1,261
Asset retirement obligations	680		731
Liabilities from risk management activities, net of collateral	98		160




Operating lease obligations	198		200
Natural gas cost over recovery	163		193
Other regulatory liabilities	196		369
Other current liabilities	970		1,100
Total current liabilities	16,726		15,993
Long-term Debt	64,621		58,768
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	12,250		11,730
Deferred credits related to income taxes	4,381		4,434
Accumulated deferred ITCs	1,994		2,056
Employee benefit obligations	955		1,011
Operating lease obligations, deferred	1,242		1,253
Asset retirement obligations, deferred	8,774		9,203


Other cost of removal obligations	2,032		2,016
Other regulatory liabilities, deferred	642		692

Other deferred credits and liabilities	1,357		1,350
Total deferred credits and other liabilities	33,627		33,745
Total Liabilities	114,974		108,506



















Total Stockholders' Equity (See accompanying statements)	38,274		36,674
Total Liabilities and Stockholders' Equity	$	153,248	$	145,180

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED)


	Southern Company Common Stockholders' Equity
	Number of Common Shares		Common Stock								Accumulated Other Comprehensive Income (Loss)
	Issued	Treasury	Par Value		Paid-In Capital		Treasury		Retained Earnings				Noncontrolling Interests			Total
	(in millions)
Balance at December 31, 2023	1,092	(1)	$	5,423	$	13,775	$	(59)	$	12,482	$	(177)		$	3,781		$	35,225
Consolidated net income (loss)	—	—	—		—		—		1,129		—			(58)			1,071
Other comprehensive income	—	—	—		—		—		—		37			—			37
Stock issued	3	—	8		53		—		—		—			—			61
Stock-based compensation	—	—	—		8		—		—		—			—			8

Dividends of $0.70 per share	—	—	—		—		—		(766)		—			—			(766)

Capital contributions from noncontrolling interests	—	—	—		—		—		—		—			9			9
Distributions to noncontrolling interests	—	—	—		—		—		—		—			(38)			(38)



Other	—	—	—		10		(2)		(1)		—			—			7
Balance at March 31, 2024	1,095	(1)	5,431		13,846		(61)		12,844		(140)			3,694			35,614
Consolidated net income (loss)	—	—	—		—		—		1,203		—			(15)			1,188
Other comprehensive income	—	—	—		—		—		—		10			—			10
Stock issued	1	—	5		85		—		—		—			—			90
Stock-based compensation	—	—	—		13		—		—		—			—			13

Dividends of $0.72 per share	—	—	—		—		—		(788)		—			—			(788)

Capital contributions from noncontrolling interests	—	—	—		—		—		—		—			2			2
Distributions to noncontrolling interests	—	—	—		—		—		—		—			(19)			(19)




Other	—	—	—		3		(2)		—		—			—			1
Balance at June 30, 2024	1,096	(1)	5,436		13,947		(63)		13,259		(130)			3,662			36,111
Consolidated net income	—	—	—		—		—		1,535		—			—			1,535
Other comprehensive income (loss)	—	—	—		—		—		—		(9)			—			(9)

Stock issued	1	—	5		79		—		—		—			—			84
Stock-based compensation	—	—	—		24		—		—		—			—			24

Dividends of $0.72 per share	—	—	—		—		—		(789)		—			—			(789)


Distributions to noncontrolling interests	—	—	—		—		—		—		—			(55)			(55)




Other	—	—	—		(2)		6		—		—			—			4
Balance at September 30, 2024	1,097	(1)	$	5,441	$	14,048	$	(57)	$	14,005	$	(139)		$	3,607		$	36,905

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

SOUTHERN COMPANY AND SUBSIDIARY COMPANIES

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED)


	Southern Company Common Stockholders' Equity
	Number of Common Shares		Common Stock								Accumulated Other Comprehensive Income (Loss)
	Issued	Treasury	Par Value		Paid-In Capital		Treasury		Retained Earnings				Noncontrolling Interests			Total
	(in millions)
Balance at December 31, 2024	1,098	(1)	$	5,446	$	14,149	$	(59)	$	13,750	$	(78)		$	3,466		$	36,674
Consolidated net income (loss)	—	—	—		—		—		1,334		—			(64)			1,270
Other comprehensive income	—	—	—		—		—		—		3			—			3
Stock issued	2	—	7		78		—		—		—			—			85
Stock-based compensation	—	—	—		5		—		—		—			—			5

Dividends of $0.72 per share	—	—	—		—		—		(791)		—			—			(791)

Capital contributions from noncontrolling interests	—	—	—		—		—		—		—			19			19
Distributions to noncontrolling interests	—	—	—		—		—		—		—			(37)			(37)



Other	—	—	—		(1)		(2)		(2)		—			—			(5)
Balance at March 31, 2025	1,100	(1)	5,453		14,231		(61)		14,291		(75)			3,384			37,223
Consolidated net income (loss)	—	—	—		—		—		880		—			(27)			853
Other comprehensive income	—	—	—		—		—		—		4			—			4
Stock issued	1	—	5		84		—		—		—			—			89
Stock-based compensation	—	—	—		11		—		—		—			—			11

Dividends of $0.74 per share	—	—	—		—		—		(815)		—			—			(815)

Capital contributions from noncontrolling interests	—	—	—		—		—		—		—			4			4
Distributions to noncontrolling interests	—	—	—		—		—		—		—			(33)			(33)




Other	—	—	—		6		(1)		1		—			—			6
Balance at June 30, 2025	1,101	(1)	5,458		14,332		(62)		14,357		(71)			3,328			37,342
Consolidated net income (loss)	—	—	—		—		—		1,711		—			(4)			1,707
Other comprehensive income (loss)	—	—	—		—		—		—		(8)			—			(8)

Stock issued	1	—	4		79		—		—		—			—			83
Stock-based compensation	—	—	—		21		—		—		—			—			21

Dividends of $0.74 per share	—	—	—		—		—		(815)		—			—			(815)


Distributions to noncontrolling interests	—	—	—		—		—		—		—			(52)			(52)



Other	—	—	1		(10)		5		1		(1)			—			(4)
Balance at September 30, 2025	1,102	(1)	$	5,463	$	14,422	$	(57)	$	15,254	$	(80)		$	3,272		$	38,274

The accompanying notes as they relate to Southern Company are an integral part of these condensed consolidated financial statements.

Table of Contents Index to Financial Statements

ALABAMA POWER COMPANY

CONDENSED STATEMENTS OF INCOME (UNAUDITED)


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2025		2024		2025		2024
	(in millions)				(in millions)
Operating Revenues:
Retail revenues	$	2,046	$	1,904	$	5,487	$	5,117
Wholesale revenues, non-affiliates	137		89		326		259
Wholesale revenues, affiliates	28		34		132		103
Other revenues	107		111		353		324
Total operating revenues	2,318		2,138		6,298		5,803
Operating Expenses:
Fuel	416		384		1,139		1,050
Purchased power, non-affiliates	56		49		180		148
Purchased power, affiliates	97		48		218		134
Other operations and maintenance	434		493		1,370		1,335
Depreciation and amortization	380		366		1,121		1,091
Taxes other than income taxes	115		108		365		347
Total operating expenses	1,498		1,448		4,393		4,105
Operating Income	820		690		1,905		1,698
Other Income and (Expense):
Allowance for equity funds used during construction	18		15		54		40
Interest expense, net of amounts capitalized	(119)		(113)		(343)		(337)
Other income (expense), net	44		36		128		116
Total other income and (expense)	(57)		(62)		(161)		(181)
Earnings Before Income Taxes	763		628		1,744		1,517
Income taxes	175		135		401		322
Net Income	$	588	$	493	$	1,343	$	1,195

CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2025		2024		2025		2024
	(in millions)				(in millions)
Net Income	$	588	$	493	$	1,343	$	1,195
Other comprehensive income:
Qualifying hedges:

Reclassification adjustment for amounts included in net income, net of tax of $—, $—, $1, and $1, respectively	1		—		2		1
Total other comprehensive income	1		—		2		1
Comprehensive Income	$	589	$	493	$	1,345	$	1,196

The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.

Table of Contents Index to Financial Statements

ALABAMA POWER COMPANY

CONDENSED STATEMENTS OF CASH FLOWS (UNAUDITED)


	For the Nine Months Ended September 30,
	2025		2024
	(in millions)
Operating Activities:
Net income	$	1,343	$	1,195
Adjustments to reconcile net income to net cash provided from operating activities —
Depreciation and amortization, total	1,226		1,201

Deferred income taxes	127		(79)

Pension, postretirement, and other employee benefits	(148)		(151)
Settlement of asset retirement obligations	(202)		(184)

Retail fuel cost under recovery – long-term	(69)		—

Other, net	(75)		24
Changes in certain current assets and liabilities —
-Receivables	(125)		(115)
-Fossil fuel stock	71		46
-Prepayments	(56)		(44)

-Retail fuel cost under recovery	(14)		236
-Other current assets	24		(32)
-Accounts payable	(286)		(304)
-Accrued taxes	237		235


-Customer refunds	(110)		(23)
-Other current liabilities	(143)		(22)
Net cash provided from operating activities	1,800		1,983
Investing Activities:
Property additions	(1,523)		(1,279)
Business acquisition	(635)		—
Nuclear decommissioning trust fund purchases	(407)		(448)
Nuclear decommissioning trust fund sales	407		448
Cost of removal, net of salvage	(137)		(123)
Change in construction payables, net of joint owner portion	(52)		(32)
Other investing activities	(14)		(26)
Net cash used for investing activities	(2,361)		(1,460)
Financing Activities:
Increase in notes payable, net	—		(40)
Proceeds —
Senior notes	1,100		—


Short-term borrowings	—		50
Other long-term debt	4		6
Redemptions —

Senior notes	(250)		—


Revenue bonds	—		(21)
Short-term borrowings	—		(50)

Capital contributions from parent company	591		488
Payment of common stock dividends	(914)		(886)
Other financing activities	(12)		(3)
Net cash provided from (used for) financing activities	519		(456)
Net Change in Cash, Cash Equivalents, and Restricted Cash	(42)		67
Cash, Cash Equivalents, and Restricted Cash at Beginning of Period	585		409
Cash, Cash Equivalents, and Restricted Cash at End of Period	$	543	$	476
Supplemental Cash Flow Information:
Cash paid during the period for —
Interest (net of $16 and $13 capitalized for 2025 and 2024, respectively)	$	347	$	356
Income taxes, net	243		288
Noncash transactions —
Accrued property additions at end of period	96		106

Right-of-use assets obtained under operating leases	8		11
Right-of-use assets obtained under finance leases	4		—

The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.

Table of Contents Index to Financial Statements

ALABAMA POWER COMPANY

CONDENSED BALANCE SHEETS (UNAUDITED)


Assets	At September 30, 2025		At December 31, 2024
	(in millions)
Current Assets:
Cash and cash equivalents	$	543	$	585
Receivables —
Customer accounts	577		512
Unbilled revenues	197		187


Affiliated	133		91
Other accounts and notes	82		126
Accumulated provision for uncollectible accounts	(22)		(22)
Fossil fuel stock	267		339
Materials and supplies	720		699

Prepaid expenses	128		63

Other regulatory assets	345		332
Other current assets	137		79
Total current assets	3,107		2,991
Property, Plant, and Equipment:
In service	38,605		36,501
Less: Accumulated provision for depreciation	12,614		11,741
Plant in service, net of depreciation	25,991		24,760
Other utility plant, net	331		410
Nuclear fuel, at amortized cost	298		262
Construction work in progress	1,412		1,377
Total property, plant, and equipment	28,032		26,809
Other Property and Investments:
Nuclear decommissioning trusts, at fair value	1,526		1,386
Equity investments in unconsolidated subsidiaries	46		48
Miscellaneous property and investments	123		129
Total other property and investments	1,695		1,563
Deferred Charges and Other Assets:
Operating lease right-of-use assets, net of amortization	82		84
Deferred charges related to income taxes	268		264
Prepaid pension and other postretirement benefit costs	922		841

Regulatory assets – asset retirement obligations	1,515		1,780
Other regulatory assets, deferred	1,914		1,815
Other deferred charges and assets	413		391
Total deferred charges and other assets	5,114		5,175
Total Assets	$	37,948	$	36,538

The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.

Table of Contents Index to Financial Statements

ALABAMA POWER COMPANY

CONDENSED BALANCE SHEETS (UNAUDITED)


Liabilities and Stockholder's Equity	At September 30, 2025		At December 31, 2024
	(in millions)
Current Liabilities:
Securities due within one year	$	624	$	655

Accounts payable —
Affiliated	302		299
Other	367		625
Customer deposits	115		113


Accrued taxes	289		78
Accrued interest	102		120

Accrued compensation	261		240

Asset retirement obligations	264		364
Other regulatory liabilities	29		165
Other current liabilities	136		219
Total current liabilities	2,489		2,878
Long-term Debt	11,381		10,499
Deferred Credits and Other Liabilities:
Accumulated deferred income taxes	4,361		4,178
Deferred credits related to income taxes	1,382		1,398
Accumulated deferred ITCs	107		113
Employee benefit obligations	150		148
Operating lease obligations	73		76
Asset retirement obligations, deferred	3,446		3,694

Other regulatory liabilities, deferred	171		271

Other deferred credits and liabilities	274		195
Total deferred credits and other liabilities	9,964		10,073
Total Liabilities	23,834		23,450









Common Stockholder's Equity (See accompanying statements)	14,114		13,088
Total Liabilities and Stockholder's Equity	$	37,948	$	36,538

The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.

Table of Contents Index to Financial Statements

ALABAMA POWER COMPANY

CONDENSED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY (UNAUDITED)


	Number of Common Shares Issued	Common Stock		Paid-In Capital		Retained Earnings		Accumulated Other Comprehensive Income (Loss)		Total
	(in millions)
Balance at December 31, 2023	31	$	1,222	$	7,125	$	3,993	$	(7)	$	12,333
Net income	—	—		—		333		—		333

Capital contributions from parent company	—	—		427		—		—		427

Cash dividends on common stock	—	—		—		(295)		—		(295)
Other	—	—		—		(1)		—		(1)
Balance at March 31, 2024	31	1,222		7,552		4,030		(7)		12,797
Net income	—	—		—		369		—		369

Capital contributions from parent company	—	—		50		—		—		50
Other comprehensive income	—	—		—		—		1		1
Cash dividends on common stock	—	—		—		(296)		—		(296)

Balance at June 30, 2024	31	1,222		7,602		4,103		(6)		12,921
Net income	—	—		—		493		—		493


Capital contributions from parent company	—	—		16		—		—		16

Cash dividends on common stock	—	—		—		(295)		—		(295)

Balance at September 30, 2024	31	$	1,222	$	7,618	$	4,301	$	(6)	$	13,135

Balance at December 31, 2024	31	$	1,222	$	7,657	$	4,214	$	(5)	$	13,088
Net income	—	—		—		375		—		375

Capital contributions from parent company	—	—		527		—		—		527
Other comprehensive income	—	—		—		—		1		1
Cash dividends on common stock	—	—		—		(305)		—		(305)
Other	—	—		—		—		(1)		(1)
Balance at March 31, 2025	31	1,222		8,184		4,284		(5)		13,685
Net income	—	—		—		381		—		381

Capital contributions from parent company	—	—		38		—		—		38

Cash dividends on common stock	—	—		—		(304)		—		(304)
Other	—	—		—		(1)		1		—
Balance at June 30, 2025	31	1,222		8,222		4,360		(4)		13,800
Net income	—	—		—		588		—		588


Capital contributions from parent company	—	—		31		—		—		31
Other comprehensive income	—	—		—		—		1		1
Cash dividends on common stock	—	—		—		(305)		—		(305)
Other	—	—		—		—		(1)		(1)
Balance at September 30, 2025	31	$	1,222	$	8,253	$	4,643	$	(4)	$	14,114

The accompanying notes as they relate to Alabama Power are an integral part of these condensed financial statements.

Table of Contents Index to Financial Statements

GEORGIA POWER COMPANY

CONDENSED STATEMENTS OF INCOME (UNAUDITED)


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2025		2024		2025		2024
	(in millions)				(in millions)
Operating Revenues:
Retail revenues	$	3,359	$	3,185	$	8,754	$	7,937
Wholesale revenues	140		78		390		198

Other revenues	271		209		774		610
Total operating revenues	3,770		3,472

SOUTHERN CO 10-Q